Plastic containers



April 16, 1963 A. FIBISH 3,085,730

PLASTIC CONTAINERS Filed May 1, 1961 1N ENTOR.

United States Patent 3,085,730 PLASTIC CONTAINERS Arthur Fibish,Prospect Heights, 11]., assignor to Illinois Tool Works Inc, acorporation of Delaware Filed May 1, 1961, Ser. No. 106,619 4 Claims.(Cl. 2291.5)

This invention relates to containers, and more particularly to a thinwalled plastic container especially useful as a drinking cup.

Disposable or throw away cups designed to be used in vending machines,and for other purposes in which the cup is to be used only once havegenerally been made of paper. Paper cups have variousdisadvantages,including taste, touch, and lack of complete liquid and vapor proofqualities even when waxed. Additionally, the glued seams which areinherently required in paper cups are often objectionable. For these,and other reasons, efforts have been made to produce disposable plasticcups. Such cups overcome the listed drawbacks of paper cups, but thematerial cost is somewhat higher.

One expedient for reducing or overcoming the inherently higher cost ofplastic material is to use less of it. For a given size of cup, thismeans that the wall thickness of the cup must be reduced. Unfortunately,reduction in wall thickness results in a concomitant reduction in wallrigidity. This is of rather considerable importance in the larger sizecups, say on the order of eight ounces or so capacity, wherein thinwalls will readily tend to bulge or bow outwardly under the pressure ofliquids in the cup, and conversely will tend to deflect inwardly underthe pressure of fingers lifting the cup. Furthermore, cups and the liketo be dispensed from automatic vending machines are subjected to acombined axial and torsional force during feeding within the machine tothe liquid receiving station.

Accordingly, it is an object of this invention to provide a thin walledcontainer, specifically a cup, requiring a lesser amount of plasticmaterial for a wall of given rigidity.

More specifically, it is an object of thi invention to provide a plasticcup having embossments in the side wall thereof with vertical,horizontal, and diagonal components, whereby to stifien the wall in aplurality of directions.

Generally speaking, it is necessary to provide draft to allow shapedplastic articles to be withdrawn from a mold. This makes it difiicult toprovide embossments in a circumferential wall, unless they can bearranged in stepwise fashion.

A further object of the present invention is to provide a plastic cuphaving an embossed side wall for stiffening the side wall, whereinadvantage is taken of the inherent resiliency of the plastic material tofacilitate withdrawal of the cup from a mold.

Other and further objects and advantages of the present invention willbe apparent from the following description when taken in connection withthe accompanying drawings wherein:

FIG. 1 is an elevational view of a cup constructed in accordance withthe principles of the present invention, and in the original patentdrawings on a scale just slightly larger than full scale;

FIG. 2 is an enlarged fragmentary elevational view approximately threetimes full scale showing details of the embossed side wall of the cup;

FIG. 3 is a horizontal sectional view through the side wall of the cupas taken substantially along the line 3-3 in FIG. 1, on an enlargedscale, approximately six times actual size;

FIG. 4 is a view similar to FIG. 3 but taken at a different elevation,as along the line 4-4 in FIG. 1; and

3,985,730 Patented Apr. 16, 1963 in accordance with the principles ofthe invention. The

cup is of generally frustoconical configuration having an outwardlytapering side wall 12 terminating at the upper end at :an open mouthsurrounded by a radially projecting rim 14, preferably in the form of arolled over lip. The bottom portion of the cup is provided with astacking ring 16 of stepped configuration adapted for supporting one cupwithin another in stacked, telescoped relation.

The side wall 12 through the greater portion of its height is providedwith an embossed herringbone or zigzag pattern of peripherally spacedalternate ribs 18 and valleys 20. The ribs project out beyond thenominal surface of the cup side wall, while the valleys are de pressedbelow the nominal surface at the uppermost portion thereof.

As may be seen particularly in FIGS. 2 and 7, each rib 18 has a roundedbottom end 22 projecting smoothly out from the subjacent section 24 ofthe side Wall 12. The rib extends diagonally up and to the right to apoint of inflection 24, and then extends up and to the left to anotherpoint of inflection, etc. At the upper end, each rib 18 (FIGS. 2, 6 and7) tapers back at 26 to the level of the immediately overlying surface28.

Conversely, the valleys 20 (FIGS. 2 and 7) start out on a level with theunderlying surfaces 24, and gradually extend inwards to the upper ends(FIG. 6) whereat they taper out at 30 to become flush with the overlyingsurface 28. The upper ends of the ribs 18 and valleys 20 form a more orless continuous line 32 extending peripherally about the cup. Althoughthe cup is shown with this line spaced down from the rim or li 14, it isto be understood that this line could be positioned considerably closer,even substantially against the rim or lip 14.

Each rib 18 has a more or less flat outer surface 34, and conversely thefloor 36 of each intervening valley is also substantially fiat. Theupper side Wall of each rib section, referring to the direction of thetop or open end of the cup, is at an obtuse angle to the more or lessflat tops and bottoms 34 and 36 of the ribs and valleys respectively,such side Wall being indicated at 38. The opposite rib side walls 40,those on the lower side of each rib section relative to the upper end ofthe cup, are close to perpendicular relative to the rib tops 34 andvalley bottoms 36.

. The disposition of the upper rib side wall 38 at a rather shallowangle relative to the cup surface is important in that it allows a cuptobe ejected from a female mold. The cup preferably is formed by acombination of mechanical and differential fluid pressure molding, andthe ribs extend into complementary recesses in the female mold.Normally, this would tend to make the cup stick in the mold. However,with the shallow angle, as aforesaid, and with the inherent flexibilityof the plastic materialof which the cup is made, the ribs simply cam orflex out of the recesses in the female mold as the cup is ejectedaxially upwards. The diverse angles of the upper and lower side walls ofthe ribs may also provide a somewhat great stiffening effect than withequal angles on both sides.

The rib configuration and inherent flexibility of the side walls,although greatly limited by the embossed ribs, militates againsttelescoped cups sticking together. In fact, it will generally be foundthat the stacking ring sections 16 cause adjacent telescoped cups to beoffset sufliciently vertically that the rib sections in large measurecross one another, thereby avoiding any tendency for the ribs to nestwithin one another. The ribs have still a further advantage,particularly considering the crossed relation thereof in telescopedcups, of providing air passages for bleeding air into the lowest cup ina stack to allow ready feeding thereof from a vending machine. As willbe apparent, if no provision were made for air to enter the spacebetween adjacent telescoped cups, it would be extremely diflicult toseparate them, and there would be substantially no tendency forgravitational dropping.

It has been found that production of a smooth walled cup havingapproximately nine fluid ounces capacity, and of a wall thicknesssuflicient to insure the requisite rigidity requires about seven gramsof material. On the other hand, a cup of equal size constructed inaccordance with the principles of the present invention, and with equalwall rigidity requires only about three and one half to four grams ofthe identical material. Such material preferably is polystyrene plastic.The wall thickness of a typical cup is on the order of .010 inch, andthe apparent or overall wall thickness in the rib and valley area aboutdoubles that of the inherent thickness of the wall.

The specific embodiment of the invention as shown and described hereinis for illustrative purposes only. Various changes in structure will nodoubt occur to those skilled in the art, and will be understood asforming a part of this invention insofar as they fall within the spiritand scope of the appended claims.

The invention is claimed as follows:

1. A thin walled nestable plastic cup-like container made from a web ofsubstantially uniform thickness material and comprising a bottom, andside wall having a substantially frustoconical configuration, said sidewall being provided with a stacking ring spaced from the bottom of saidcup, said side wall being provided at the other end of said cup oppositesaid bottom with a thickened lip portion intended to rigidify the sidewall of said cup in the vicinity of the mouth of the container, at leasta portion of the side wall intermediate said stacking ring and saidthickened lip portion having impressed thereon an embossed herringbonepattern having a pluarlity of channel shaped ribs equally spacedcircumferentially on said side wall, portions of said pattern extendingradially outwardly beyond and other portions extending radially inwardlybeyond a medial plane interconnecting the aforementioned thickened lipportion and said stacking ring and affording an apparent wall thicknesssubstantially heavier than the web from which the container isfabricated, each rib of said embossed pattern having a zig zagconfiguration extending generally axially of the container with adjacentsections in each rib extending alternately on opposite sides of avertical line running generally axially of said container and thematerial thickness of said bottom and side walls including said embossedpatern being substantially uniform whereby said pattern substantiallyrigidifies said side walls against axial compression and torsionalforces.

2. A device of the type claimed in claim 1 wherein each rib in saidpattern includes in the portion of said pattern extending radiallyoutwardly as viewed in trausverse section a flat top surface and twoside edges, the side edge of each section of the rib which are disposedrelatively toward the top of the container forming a shallow angle witha plane passing through said top surface and the aforementioned medialplane and the opposite side edge being disposed substantially normal tothe top surface and medial plane whereby said container can be readilyejected from a female mold.

3. A device of the type claimed in claim 1 wherein the spacing andangular disposition of sections of adjacent ribs is controlled so that avertical line placed on the side wall and lying generally parallel tothe axis of the container will pass through sections of more than onerib whereby the overlying configuration of channel shaped ribssubstantially rigidifies an otherwise weak and collapsable container.

4. A plurality of thin walled plastic cup-like containers adapted to betelescoped into stacked nested relation, each container being made froma web of substantially uniform thickness material and including a bottomand a side wall extending upwardly from said bottom, said side wallhaving a substantially frustoconical configuration, stacking means insaid side wall spaced from the bottom of said container, said sidewallbeing provided at the end of said container opposite said bottom with athickened lip portion intended to rigidify the side wall in the vicinityof the mouth of the container, at least a portion of the side wallintermediate said stacking ring and said thickened lip portion havingimpressed thereon an embossed herringbone pattern including a pluralityof "channel shaped ribs equally spaced circumferentially about said sidewall, portions of said pattern extending radially outwardly beyond andother portions extending radially inwardly beyond a medial planeinterconnecting the aforementioned thickened lip portion and saidstacking ring, each rib of said embossed pattern having a zig zagconfiguration of sections extending angularly first to the right to apoint of inflection and then to the left to a point of inflection andcontinuing alternately to the terminal end of the rib, the zig zag ribextending generally axially of the container, adjacent sections in eachrib extending alternately on opposite sides of an imaginery verticalline running generally axially of said container, said stacking meansbeing adapted to maintain the bottoms of adjacent containers in spacedrelation and causing the rib sections of adjacent cups to be offsetsufliciently vertically so that a rib section of one cup extendingangularly to the right will overlie a rib section of the next adjacentcup extending angularly to the left thereby preventing nesting of onerib within another and elimination of jamming of stacked containers,said channel shaped ribs providing passageways for air between adjacentcups to assist in the separation of the terminal container from a stackof nested containers.

References Cited in the file of this patent UNITED STATES PATENTS D.18,225 Barr Apr. 3, 1888 2,352,205 Karlson June 27, 1944 2,905,350Edwards Sept. 22, 1959 2,915,176 ONeil Dec. 1, 1959 2,967,652 Canfieldet al Jan. 10, 1961 3,029,963 Evers Apr. 17, 1962 FOREIGN PATENTS 17,971Great Britain 1894

1. A THIN WALLED NESTABLE PLASTIC CUP-LIKE CONTAINER MADE FROM A WEB OFSUBSTANTIALLY UNIFORM THICKNESS MATERIAL AND COMPRISING A BOTTOM, ANDSIDE WALL HAVING A SUBSTANTIALLY FRUSTOCONICAL CONFIGURATION, SAID SIDEWALL BEING PROVIDED WITH A STACKING RING SPACED FROM THE BOTTOM OF SAIDCUP, SAID SIDE WALL BEING PROVIDED AT THE OTHER END OF SAID CUP OPPOSITESAID BOTTOM WITH A THICKENED LIP PORTION INTENDED TO RIGIDIFY THE SIDEWALL OF SAID CUP IN THE VICINITY OF THE MOUTH OF THE CONTAINER, AT LEASTA PORTION OF THE SIDE WALL INTERMEDIATE SAID STACKING RING AND SAIDTHICKNED LIP PORTION HAVING IMPRESSED THEREON AN EMBOSSED HERRINGBONEPATTERN HAVING A PLURALITY OF CHANNEL SHAPED RIBS EQUALLY SPACEDCIRCUMFERENTIALLY ON SAID SIDE WALL, PORTIONS OF SAID PATTERN EXTENDINGRADIALLY OUTWARDLY BEYOND AND OTHER PORTIONS EXTENDING RADIALLY INWARDLYBEYOND A MEDIAL PLANE INTERCONNECTING THE AFOREMENTIONED THICKENED LIPPORTION AND SAID STACKING RING AND AFFORDING AN APPARENT WALL THICKNESSSUBSTANTIALLY HEAVIER THAN THE WEB FROM WHICH THE CONTAINER ISFABRICATED, EACH RIB OF SAID EMBOSSED PATTERN HAVING A ZIG ZAGCONFIGURATION EXTENDING GENERALLY AXIALLY OF THE CONTAINER WITH ADJACENTSECTIONS IN EACH RIB EXTENDING ALTERNATELY ON OPPOSITE SIDES OF AVERTICAL LINE RUNNING GENERALLY AXIALLY OF SAID CONTAINER AND THEMATERIAL THICKNESS OF SAID BOTTOM AND SIDE WALLS INCLUDING SAID EMBOSSEDPATERN BEING SUBSTANTIALLY UNIFORM WHEREBY SAID PATTERN SUBSTANTIALLYRIGIDIFIES SAID SIDE WALLS AGAINST AXIAL COMPRESSION AND TORSIONALFORCES.